A blood clot in a deep vein of the leg, called Deep vein thrombosis, can be serious because part of the clot can travel to the lungs and cause a Pulmonary embolism.
10 Warning Signs of a Blood Clot in the Leg
- Swelling in one leg
- Often affects the calf or thigh and usually occurs on only one side.
- Pain or tenderness
- May feel like a cramp, soreness, or aching, often in the calf.
- Warmth over the affected area
- The skin may feel warmer than the surrounding areas.
- Red or discolored skin
- The leg may appear red, purple, or darker than usual.
- Pain when standing or walking
- Symptoms may worsen with movement or when putting weight on the leg.
- A swollen vein
- Surface veins may appear larger or more noticeable.
- A feeling of tightness or fullness
- The affected leg may feel heavy or tight.
- Tenderness when touching the calf
- Pain may be localized to a specific area.
- One leg larger than the other
- A noticeable difference in calf or thigh size can be a warning sign.
- No symptoms at all
- Some deep vein thromboses cause few or no noticeable symptoms and are discovered only after complications develop.
Risk factors
You may be at higher risk if you:
- Have recently had surgery or a major injury
- Have been immobile for a long time (such as during a long flight or bed rest)
- Are pregnant or recently gave birth
- Have cancer
- Smoke
- Take estrogen-containing medications
- Have a personal or family history of blood clots
Seek emergency medical care immediately if you have leg symptoms plus:
- Sudden shortness of breath
- Chest pain that worsens with breathing
- Coughing up blood
- Fainting or feeling like you might faint
These symptoms could indicate a pulmonary embolism, which is a medical emergency.
It’s important to remember that leg pain or swelling is much more commonly caused by conditions other than a blood clot, such as muscle strains, varicose veins, or injuries. However, because a DVT can be dangerous, new one-sided leg swelling or pain without an obvious cause should be evaluated promptly by a healthcare professional. Diagnosis usually requires an examination and, if needed, an ultrasound of the leg.
